Russia has warned that new American sanctions against Iran could seriously damage efforts to enforce an international agreement with Tehran over its nuclear program, slamming Washington’s newest bid against Tehran.

The development comes as the administration of US President Barack Obama issued on Thursday new sanctions against more than a dozen companies and individuals for “providing support” for Tehran’s nuclear program.

The US Treasury Department said it was freezing assets and banning transactions of entities that attempt to evade the sanctions against Iran.

Moscow criticized Washington’s efforts, saying that increased sanctions did not strengthen confidence in the negotiation process between Iran and the Group of Six nations, including Russia and the US, to reach a final agreement over the nuclear issue.

“An expansion of sanctions might seriously complicate the implementation of the Geneva agreement,” said Maria Zakharova, deputy spokesperson for the Russian Foreign Ministry.

Iran censured the US for breaking the spirit of the agreement reached in Geneva last month to restrict its nuclear activities in return for an easing of economic sanctions.